Halteres are small, club-shaped structures found in certain insects, particularly in the order Diptera, which includes flies and mosquitoes. They are modified hindwings that help these insects maintain balance and stability during flight. When a fly flaps its wings, the halteres vibrate, providing sensory feedback that allows the insect to make quick adjustments to its body position. These unique appendages play a crucial role in the agility of flying insects. By sensing changes in orientation and movement, halteres enable insects to perform complex aerial maneuvers, such as sharp turns and rapid stops, making them highly effective fliers in their environments.